ios - 参数类型 'UITextField' 不符合预期类型 'Sequence'

Question

这个问题已经有答案了:

Why do I get the error "Argument type 'String' does not conform to expected type 'sequence' (2 个回答)

已关闭 4 年前。

我目前正在观看 YouTube 视频，了解我正在开发的应用程序的用户注册信息。我试图在您输入密码的地方创建两个文本字段以进行匹配。代码如下:

@IBAction func signUpButtonTapped(_ sender: Any) {
    print("Registrer ny bruker")

    // Validate required fields are not empty
    if (firstNameTextField.text?.isEmpty)! ||
        (lastNameTextField.text?.isEmpty)! ||
        (emailAdressTextField.text?.isEmpty)! ||
        (passwordTextField.text?.isEmpty)!
    {
        // Display alert message and return
        return
    }

    // Validate password
    if ((passwordTextField.text?.elementsEqual(repeatPasswordTextField!))! != true) {
        return
    }        
}

在“验证密码”上我得到:

Argument type 'UITextField' does not conform to expected type 'Sequence'

我是新手，非常感谢您的帮助。

Answer 1

欢迎来到 StackOverflow。您遇到的问题是因为您试图查看字符串是否包含 UITextField。

我们可以让它变得更优雅:

@IBAction func signUpButtonTapped(_ sender: Any) {
    print("Registrer ny bruker")

    guard let firstName = firstNameTextField.text,
      let lastName = lastNameTextField.text,
      let email = emailAdressTextField.text,
      let password = passwordTextField.text,
      let repeatedPassword = repeatPasswordTextField.text else {
          // If any of the values above is empty, just return
          return
      }

    // We avoid force unwrapping with the guard above
    // so the values we test for here are not optional 
    if firstName.isEmpty ||
       lastName.isEmpty ||
       password.isEmpty ||
       repeatedPassword.isEmpty {
        // Display alert message and return
        return
    }

    // Validate password
    if password != repeatedPassword {
        return
    }

}

希望这有帮助。